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排序方式: 共有1319条查询结果,搜索用时 15 毫秒
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An advanced prototype Computer Controlled Power Wheelchair Navigation System or CCPWNS has been developed to provide autonomy for highly disabled users, whose mix of disabilities makes it difficult or impossible to control their own power chairs in their homes. The working paradigm is “teach and repeat” a mode of control for typical industrial holonomic robots. Ultrasound sensors, which during subsequent autonomous tracking will be used to detect obstacles, also are active during teaching. Based upon post-processed data collected during this teaching event, elaborate trajectories–which may involve multiple direction changes, pivoting and so on, depending upon the requirements of the typically restricted spaces within which the chair must operate–will later be called upon by the disabled rider. An off-line postprocessor assigns an ultrasound profile to the sequence of poses of any taught trajectory. Use of this profile during tracking obviates most of the inherent problems of using ultrasound to avoid obstacles while retaining the ability to near solid objects, such as when passing through a narrow doorway, where required by the environment and trajectory objectives. The work in this article describes a procedure to obtain consistent maps of sonar boundaries during the teaching process, and a preliminary approach to use this information during the tracking phase. The approach is illustrated by results obtained by using the CCPWNS prototype. 相似文献
73.
吕向阳 《陕西科技大学学报》2002,20(3):65-66
介绍了在生产特种纸和纸板时可选用的高线压底网造纸毛毯和化学处理底网造纸毛毯的使用性能,并指出加强其洗涤与维护对生产的重要性。 相似文献
74.
蒋寅 《兰州工业高等专科学校学报》2002,9(3):5-8
针对多媒体课件在现代教育中的一些应用问题,详细介绍了MMB这个新颖的多媒体制作工具的功能及特点。使用MMB实现了制作教学课件快捷、高效、简便。此外,还介绍了MMB使用中的一些技巧。 相似文献
75.
先宁 《重庆科技学院学报(社会科学版)》2002,17(4):63-64
通过分析大学英语课堂教学存在的误区 ,找出目前大学英语教学现状的症结 ,探索新的英语课堂教学模式 ,以培养社会所需的实用性英语人才 相似文献
76.
在论述工程资金使用计划编制重要性的基础上,讨论了如何编制工程资金使用计划,如 何在工程实施过程中利用工程预算费用曲线、实际投入费用曲线及预算费用和时间关系曲线进行 投资偏差分析,进而实现进度成本双控制等。 相似文献
77.
The authors discussed to what degree testimony from social science and mental health experts (psychologists, psychiatrists, social workers, therapists, others) meets admissibility requirements expressed by the U.S. Supreme Court in Daubert (1993), Joiner ( General Electric Co. v. Joiner , 1997) and the recent Kumho (1999) decision. They reviewed data on Daubert/Kumho indicia of reliability using 2 exemplar areas of mental health testimony: psychodiagnostic assessment by means of the Rorschach and other "projective" assessment techniques and the diagnoses of posttraumatic stress disorder and multiple personality disorder (dissociative identity disorder). They concluded that some testimony offered by mental health professionals relating to these concepts should not survive scrutiny under the framework of Daubert , Joiner , and Kumho . (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Schmitt Neal; Oswald Frederick L.; Kim Brian H.; Imus Anna; Merritt Stephanie; Friede Alyssa; Shivpuri Smriti 《Canadian Metallurgical Quarterly》2007,92(1):165
To determine whether profiles of predictor variables provide incremental prediction of college student outcomes, the authors 1st applied an empirical clustering method to profiles based on the scores of 2,771 entering college students on a battery of biographical data and situational judgment measures, along with SAT and American College Test scores and high school grade point average, which resulted in 5 student groups. Performance of the students in these clusters was meaningfully different on a set of external variables, including college grade point average, self-rated performance, class absenteeism, organizational citizenship behavior, intent to quit their university, and satisfaction with college. The 14 variables in the profile were all significantly correlated with 1 or more of the outcome measures; however, nonlinear prediction of these outcomes on the basis of cluster membership did not add incrementally to a linear-regression-based combination of these 14 variables as predictors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Optimizing queries using materialized views has not been addressed adequately in the context of XML due to the many limitations associated with the definition and usability of materialized views in traditional XML query evaluation models. 相似文献